Year current US$ 1995 7420000000 1996 7626000000 1997 6987000000 1998 6814000000 1999 5767000000 2000 5746000000 2001 5451000000 2002 5841000000 2003 7287000000 2004 8561000000 2005 9287000000 2006 9728000000 2007 10634000000 2008 11464000000 2009 11529000000 2010 11805000000 2011 14533000000 2012 16018000000 2013 17024000000 2014 17781000000 2015 17207000000 2016 17619000000 2017 19099000000 2018 19054000000 2019 18754000000 2020 9546000000